Nitramines, nitrosamines and their preparation



United States Patent 3,098,873 NITRAMKNES, NITROSAMINES AND THEIR PREPARATION Milton B. Frankel, Pasadena, and Karl Klager, Monrovia, Caiif., assignors to Aerojet-General Corporation, Azusa, Calif., a corporation of Ghio No Drawing. Filed June 13, 1957, Ser. No. 666,274 19 Claims. (Cl. 260-583) This invention relates to new compositions of matter and to the preparation thereof. More specifically, the invention relates to high energy nitramines and nitrosamines having the following general formula:

and particularly to such high energy dinitramines of the following general formula:

wherein R is a hydrogen, alkyl, or nitroalkyl radical; A is an alkylene radical; X is a nitroso or a nitro radical; and R is a hydrogen, nitro, alkyl, or nitroalkyl radical.

The high energy nitramines and nitrosamines of this invention are useful as high explosives and can be used in any conventional explosive missile, projectile, rocket, or the like, as the main explosive charge. An example of such a missile is disclosed in United States Batent No. 2,470,162, issued May 17, 1949. One Way of using the high explosives of this invention in a device such as that disclosed in United States Patent No. 2,470,162, is to pack the crystalline explosive in powder form into the warhead of the missile. Alternatively, the crystals can be first pelletized and then packed. A charge thus prepared is suffi'ciently insensitive to withstand the shock entailed in the ejection of a shell from a gun barrel or from a rocket launching tube under the pressure developed from ignition of a propellant charge, and can be caused to explode on operation of an impactor time fusemechanism firing a detonating explosive such as lead azide or mercury fulminate.

The high energy dinitramines of this invention are prepared by reacting nitramines with nitric acid, preferably in the presence of sulfuric acid, in accordance with the general reaction scheme set forth below:

wherein R is a hydrogen, alkyl or nitroalkyl radical; A is an alkylene radical; and R is a hydrogen, nitro, alkyl, or nitroalkyl radical.

The nitrosamines of this invention are prepared by reacting an amine with nitric acid in the presence of acetic anhydride in accordance with the general reaction scheme set forth below:

3,998,873 Patented July 23, 1963 mice 7 2 wherein A, R and R 'are as defined above. An alternate method of preparing the nitrosamines of this invention is to react an amine such as that shown in the above re action scheme with nitrous acid (HNOg). The nitrosamines thus obtained are useful as high explosives as noted labove and also serve as starting materials in an alternative method of preparing the nitramines of this invention. The nitrosamines of this invention react with nitric acid in the presence of sulfuric acid to yield the nitramines of this invention in accordance with the following general reaetion scheme:

NO; NO N02 R-CH D'I-A-OH H2504 To more clearly illustrate our invention, the following examples are presented. It should be understood that these examples are presented merely as a means of illustration and are not intended to limit the scope of the invention in any Way.

Example I.-Preparation of 3,6-Diaza-3-Nitr0s0- 1,1,1,6-Tezranitr0heptane A solution of 29.0 g. (0.1 mole) of 3,6-diaza-1,1,1,6- tetranitroheptane in ml. of acetic anhydride was added dropwise to 100 ml. of 100% nitric acid while keeping the temperature of said acid at 0-5 C. The resulting mixture was poured on ice to yield an oil which crystallized to a cream colored solid. The solid was collected, washed with water, and dried in vacuo over potassium hydroxide, thus producing 12.8 g. (41.2%) of 3,6-diaza-3-nitroso-1,1,1,6-tetranitroheptane product. Recrystallization from ethylene dichloride gave white needles, M.P. 131-132 C. The compound gave a positive Leiberman test for the nitroso group.

Analysis-Calculated for C H N O percent C, 19.30; percent H, 2.92; percent N, 31.51. Found: percent C, 20.20; percent H, 2.95; percent N, 31.27.

Example II.-Preparation of 3,6 -Diaza-1,1,1,3,6- Pentanitroheptane A mixture of 35 ml. of 100% nitric acid, 25 ml. of concentrated sulfuric acid, and 3.6 g. (0.011 mole) of 3,6- diaza-3-nitroso-1,1,1,6-tetranitroheptane Was prepared. The solution was held at 50-55 C. for 30 minutes, cooled, and poured on ice. A white solid was collected, washed with water, and dried in vacuo over potassium hydroxide to yield 3.5 g. (92.5%) of 3,6-diaza-1,1,1,3,6- pentanitrcheptane product having a M.P. of 132-135 C. Recrystallization from ethylene chloride raised the M.P. to 134 135 C.

Analysis.Calculated for C5H9N7010: percent C, 18.35; percent H, 2.77; percent N, 29.27. Found: percent C, 18.86; percent H, 2.68; percent N, 30.02.

Example III.Preparati0n of 3,6-Diaza-1,1,1,3,6- Pentanitroheptane Reaction temperatures are not critical in the practice of this invention and can be varied over Wide ranges, the only effect of temperature variations being a corresponding increase or decrease in reaction rate.

It is preferred, however, in the case of nitration reactions conducted in the presence of acetic .anhydride according to this invention to maintain the reaction temperature between about and about C. due to the occurrence of undesirable side reactions which tend to reduce the yield of the desired product.

Sulfuric acid and acetic anhydride are dehydrating agents and their usefulness in the reactions of our invention derives from the fact that they take up water of reaction thus, in effect, shifting the reaction equilibrium to the right and thereby increasing product yields.

Since the sulfuric acid functions as a dehydrating agent, it should, for best results, be used in concentrated rather than dilute formexcess Water in the reaction system obviously lowers the efficiency of the sulfuric acid as a dehydrating agent.

It is interesting to note that the use of acetic anhydride as a dehydrating agent in the practice of our invention promotes the conversion of the nitramine starting materials to their corresponding nitrosamine nitramine compounds whereas the use of sulfuric acid as a dehydrating agent promotes the conversion of the nitramines to their corresponding dinitrarnine compounds. Our invention is not limited to the use of acetic anhydride and/ or sulfuric acid as dehydrating agents, other substances known to those skilled in the art as dehydrating agents may also be used within the scope of the invention. For example, relatively weak dehydrating agents such as phosphoric acid or lower organic acid such as butyric acid, propionic acid, etc., anhydrides can be used to convert the nitramine starting materials to their corresponding nitrosamines or strong dehydrating agents such as trifluoroacetic anhydride, phosphoric anhydride, etc. can be used to convert the nitramines to their corresponding dinitramines.

The nitramines used as starting materials for the preparation of the high energy nitramines of the present invention are prepared by condensing nitraza amines, as, for example, 3-nitraza-l-butylamine, with B-geminal polynitro alcohols, such as 2,2,2-trinitro ethanol, as more fully disclosed in our copending US. patent application Serial No. 666,276, filed concurrently with the present application.

It will be appreciated that a wide variety of compounds can be prepared in accordance with the teachings of our invention. For example, 3,7-diaza-1,1,7-trinitrononane; 4,7-diaza-2,2,7,9,9-pentanitrodecane; and 5,8- diaza-l,1,3,3,8-pentauitronona11e react with nitric acid in the presence of concentrated sulfuric acid to produce 3,7 diaza 1,1,3,7 -tetranitrononane; 4,7-diaza-2,2,4,7, 9,9-hexanitrodecane; and 5,8-diaza-l,1,3,3,5,8-hexanitrononane, respectively. On the other hand, 3,7-diaza-1,l,7- trinitrononane; 4,7-diam-2,2,7,9,9-pentanitrodecane; and 5 ,S-di-aza-1,1,3,3,8-pentanitrononane react with nitric acid in the presence of acetic anhydride to yield 3,7-diaza-3- nitroso-1,1,7-trinitrononane; 4,7-diaza-4-nitroso-2,2,7,9,9- pentanitrodecane; and 5,8-diaza-5-nitroso-1,1,3,3,8-pentanitrononane, respectively. Other members of this new series of compounds are prepared simply by reacting appropriate starting materials under appropriate conditions depending upon whether or not the nitro or nitroso derivative is desired.

We claim:

1. As a composition of matter, a dinitramine having the general formula:

wherein R is a lower alkyl radical and A is a lower alkylene radical.

2. As a composition of matter, 3,6-diaza-1,l,1,3,6- pentanitroheptane having the structural formula:

3. As a composition of matter, 3,7-diaza-1,l,3,7-tetranitrononane having the structural formula:

4. As a composition of matter, 4,7-diaza-2,2,4,7,9,9- hexanitrodecane having the structural formula:

5. As a composition of matter, 5,8-diaza-1,1,3,3,5,8- hexanitrononane having the structural formula:

6. As a composition of matter, 3,6-diaza-3-ni-troso-1,1, 1,6-tetranitroheptane having the structural formula:

7. As a composition of matter, 3,7-diaza-3-nitroso-1, 1,7-trinitrononane having the structural formula:

8. As a composition of matter, 4,7-diaza-4-nitroso-2,2, 7,9,9-pentanitrodecane having the structural formula:

9. As a composition of matter, 5,8-di aza-5-nitroso- 1,1,3,3,8-pentanitrononane having the structural formula:

10. The method of preparing a high energy nitramine having the general formula:

with nitric acid; wherein R is a radical selected from the group consisting of hydrogen, lower alkyl, and 'lower nitroalkyl radicals; A is a lower alkylene radical; X is a radical selected from the group consisting of nitroso and nitro radicals; and R is a radical selected from the group consisting of hydrogen, nitro, lower alkyl and lower nitroalkyl radicals.

11. The method of preparing 3,6-diaza-3-nitroso-1,1,1, 6-tetranitroheptane comprising reatcing 3,6-diaza-l,1,1,6- tetranitroheptane with nitric acid in the presence of acetic anhydride.

12. The method of preparing 3,6-diaza-1,1,1,3,61pentanitroheptane comprising the steps of reacting 3,6-diaza-1, 1,1,6-tetranitr0heptane with nitric acid in the presence of 5 acetic anhydride to obtain 3,6-diaza-3-nitroso-1,1,1,6-tetranitroheptane and reacting said 3,6-diaza-3-nitroso-1,1,1, G-tetranitroheptane with nitric acid in the presence of sulfuric acid.

13. The method of preparing 3,6-diaz-a-1,1,1,3,6-pentanitroheptane comprising reacting 3,6-diaza-1,1,1,6-tetranitroheptane with nitric acid in the presence of sulfuric acid.

14. The method of preparing 3,7-diaza-1,1,3,7-tetrar1itrononane comprising reacting 3,7-di aza-1,1,7-trinitrononane with nitric acid in the presence of sulfuric acid.

15. The method of preparing 4,7-diaza-2,2,4,7,9,9-hexanitrodecane comprising reacting 4,7-diaza-2,2,7,9,9-pentanitrodecane with nitric acid in the presence of sulfuric acid.

16. The method of preparing 5,8-diaza-1,1,3,3,5,8-heX- anitrononane comprising reacting 5,8-diaza-1,1,3,3,8-pentanitrononane with nitric acid in the presence of sulfuric acid.

17. The method of preparing 3,7-diaza-3-nitroso-1,1,7-

trinitrononane comprising reacting 3,7-diaza-1,1,7-trinitrononane with nitric acid in the presence of acetic anhydride.

18. The method of preparing 4,7-diaza-4-nitroso-2,2, 7,9,9-pentanitrodecane comprising reacting 4,7-diaza-2,2, 7,9,9-pentanitrodecane with nitric acid in the presence of acetic anhydride.

19. The method of preparing 5,8-diaza-5-nitroso-1,1, 3,3,8-pentanitrononane comprising reacting 5,8-diaza-1,1, 3,3,8-pcntanitron0nane with nitric acid in the presence of acetic anhydride. 

1. AS A COMPOSITION OF MATTER, A DINITRAMINE HAVING THE GENERAL FORMULA: 